Liquid vs. Bar in Dr. Bronner’s Pure Castile Soap

The liquid came first – peppermint to be exact. Bar soap meandered in a few decades later. While there are hardliners in both camps, the difference between liquid and bar is mostly a matter of personal preference. However, there are some differences between the two.

Here are the ingredients side by side for the unscented Baby Mild castile soap. I chose our simplest soap, which lacks any essential oils, so that the differences are easier to see.

Comparison of Liquid vs. Bar Castile Soaps

Differences explained:

  • Liquid contains more water.
    • Why: There is just enough water in the liquid soaps to keep them liquid. Any less water and the soap begins to solidify. To test this, leave the cap off your bottle for a day, and you’ll notice the soap’s starting to gel. You can reliquify it with a bit of water. (The thickness, or thinness, of the soap is not due to high water content, but to the consistency of the various oils.)
    • Effect on Performance: None
  • Liquid uses potassium hydroxide to saponify oils; bar uses sodium hydroxide.
    • Why: Hardness – sodium hydroxide produces a harder soap than potassium hydroxide. The purpose of these strong alkalis is to blast apart the oil molecules, separating the glycerin from the fatty acids. The fatty acids then reattach to the sodium or potassium ion, leaving the glycerin and water (hydroxide) free-floating. (Just a sidenote – soap cannot be made any other way. None of these alkalis are left in the soap. Check out the link at the bottom about soapmaking.)
    • Effect on Performance: None
  • Bar contains palm oil, in addition to coconut oil.
    • Why: Palm oil hardens more than coconut oil. Coconut oil, even in its solid state, is mushy, and it melts at 76° F.
    • Effect on Performance: Bar soap is slightly more moisturizing. Palm oil contains stearic acid, which some people find to be less drying than the lauric acid found in coconut oils.
  • Bar contains salt (NaCl – sodium chloride or table salt).
    • Why: Also serves as a hardener.
    • Effect on Performance: Bar soap is slightly more moisturizing. Since our bodies are slightly salty, salt water is gentler on our skin than pure water. Salty soap is, too.

Other Differences in Formulation:

  • How the Hemp and Jojoba oils are added:
    • In the liquid soaps, the hemp and jojoba oils are saponified, i.e. turned into soap, along with the coconut and olive oils. However, in the bar soaps, these two oils are added unaltered after the saponification process. This is called “superfatting” the soaps. A while back my brothers tried superfatting the liquids with the hemp and jojoba oils, but found that the oils separated out and floated to the top.
    • Effect on Performance: Bar soaps produce a creamier lather and are slightly more moisturizing.
  • Amount of Essential oils:
    • This is only relevant to the scented soaps (everything except the unscented Baby Mild). The liquid soaps have a higher percentage of the essential oils than do the bar soaps. Once again, the issue at stake is hardness. The bar soaps would soften with that high a concentration of the essential oils.
    • Effect on Performance: This is entirely a matter of personal preference. Those who like an intense whiff of scent, and those who are looking for the specific benefits of the particular essential oils, should opt for the liquids. Those who like a little scent, but not too much, the bar soap would be better.

Differences in usage:
For all body applications, they are entirely interchangeable – from washing face, hair, or body, or shaving. For around the house purposes, you would need to take the extra step of dissolving the bar soaps in water before using them in a spray bottle solution, but they are equally effective. Also, the bar soap can be grated to achieve a kind of powdered soap for laundry, although the liquid works just as well.

Volume of actual soap:
I don’t know how to de-math this, but people who put together their own recipes for cleaners might want to know this. Bar soaps are 5% water; liquids are 61%. The chemistry is a little different for both, but considering that a bar of soap weighs 5 oz, and thus 4.75 oz of it is soap, you would need 12.18 ounces (a little over 1 ½ c.) of liquid soap to equal the soap content of a 5 oz bar. Doing the math the other way, 1 cup of liquid soap equals approximately 2/3 of a bar (or 3.64 oz.) of Dr. B’s bar soap.

Bottom Line:
The Dr. Bronner’s Bar and Liquid Pure Castile soaps are interchangeable. However, the bars are slightly more moisturizing. The liquids are slightly more scented.

If you want more info on the process of soapmaking, check out this article:

If you have any other questions about what is in the soap and why or where it is sourced and why or anything else, let me know!

234 thoughts on “Liquid vs. Bar in Dr. Bronner’s Pure Castile Soap

  1. Hi Lisa, I’ve heard that castile soap can clog HE washers’ feeder hose. Would Dr. Bronner’s castile soap damage HE washers? Thanks!

    • Hi JZ – I am relying on word of mouth here since I don’t have an HE machine. Other customers have said that they have used it with no problem as long as vinegar is included in the rinse cycle. Because of my local hard water, I opt for Sal Suds in the laundry, and this doesn’t have the hard water issue that the castile soap does. Use 1-2 Tbsp.

  2. Listed above it shows that the liquid baby unscented soap does not have palm kernel oil, but when you search the product on your website, palm kernel oil IS listed as one of the ingredients. I am wondering which is true? Thanks again!

    • Hi Lauren – Thanks for pointing that out! I’m the one who is out of date. I wrote this four years ago and we just started adding palm kernel oil to our soaps this year. If palm oil or palm kernel oil gives you pause, check out how we’re sourcing it ethically and sustainably through our Fair Trade sister company Serendipalm in Ghana. Good stuff is happening here:

  3. Hi lisa!
    I have a bar of your soap here and I’m trying to figure out how to make it liquid. To use as a body wash for my babies. I boiled water but the chips didn’t melt all the way. Also wondering, is vegetable glycerin really nessacary? Or if I continue to boil water to melt them down until they are, is that fine too?? I don’t really know what I’m doing just trying to get a body wash made that I can add lavender and frankincense too. Thank you!

    • Hi Chiane – Funny you should mention this because I was just trying to do this myself. Like you, I discovered that it’s really hard to liquify our bar soap! I had to add over 6 times the amount of water as that of the soap and I still had to boil it a long time and let it sit overnight. Even then, when it cooled, it didn’t really stay liquid. it gelled up a lot. It probably could have used some more diluting. So, all this to say, liquifying the soap is not a terribly easy thing to do, but it is still possible. If it does end up being too much work for you, check out our liquid Pure Castile soaps.

  4. I’ve heard that glycerine can be drying/irritating. I have very sensitive skin. You note that glycerine is in the soap but it’s not listed in the ingredients.

    • Hi Anne – Glycerin is a natural byproduct of the soapmaking reaction. Here’s how it gets there: soap is made from oils, coconut, olive, and palm oils in our case. An oil molecule is made up of three fatty acid chains attached to one glycerin molecule. During the soapmaking reaction, the fatty acids are blasted off of that glycerin backbone by a strong alkali, such as sodium or potassium hydroxide. The fatty acids combine with the sodium or potassium, forming a soap molecule. The hydroxide ion forms water, and the glycerin is left free floating. It’s not listed in our ingredients because we don’t add it. It’s part of the oils that are listed in the ingredients. Some soapmakers drain off this glycerin and sell it separately, but we prefer to leave it in there because it actually makes for a much softer afterfeel. It will not irritate or dry your skin.

    • Hi Karen – Yep! It’s a great option for dogs.

  5. Is there enough essential oil in your soaps… lavender, tea tree, orange, peppermint to “kill” germs or do I need to add more oils for this effect when using it for household uses?

    • Hi Tee – None of the essential oils in our soaps are strong enough alone to kill bacteria outright. However, the soap itself is your main warrior here. Soap gets rid of bacteria by attaching to it and water and getting it rinsed away. If you’d like an extra antibacterial punch, add 1/2 tsp. of pure essential tea tree oil. Killing germs is not so much the need as getting rid of them. This is because attempting to kill all germs is backfiring tremendously as shown by the well-documented rise of antibacterial resistant superbugs. Here’s one of many articles on this: Hope this helps!

    • Thank you for your reply, Lisa. You are correct, I do NOT want to kill ALL bacteria as there are healthy bacteria. The healthcare profession still uses alcohol or other agents constantly that do kill bacteria before and after patient care. I do a LOT of yard work, clean my toilets, take care of my children then they are ill and pick up dog waste, albeit, with a bag, but I do not want to potentially get “bad” bacteria where it becomes a potential risk to my family’s health. I will keep a small container of your soap and add additional tea tree oil for cleaning my hands and toilets at times when I feel there is possible health risk. Thanks again! 🙂

  6. HI Lisa,

    I’m wondering if Dr. Bonner’s glycerin soap can be used to clean waxed or oiled canvas luggage without damaging the finish. The luggage in question is Filson.

    • Hi Joanne – I don’t have experience with this and I don’t want to lead you wrong. If the manufacturers instructions say something about using a “mild soap or detergent”, then our Castile or Sal Suds would be an excellent choice.

  7. Hello! Recently I got some liquid organic castile soap and I was wondering weather I can transform it into bar soap.

    I would love to make some lovely organic bar soaps and I don`t know how to make them. Could you please advice me. Many thanks and regards.

    • Hi Juliana – Because the ingredients in the liquid soap are not conducive to hardening fully, it is not really possible to create a bar soap out of it. I have never made homemade bar soaps, although there a plethora of recipes online to do so. I’m sorry not to be of more help.

      Perhaps other readers here have some suggestions?

  8. Do your bottles come sealed? I recently ordered hair rinse and the bottled came unsealed and had leaked in the packaging. I wondered if it was still safe to use or if I should throw it away.

    • Hi Jenn – I’m so sorry to hear this and that I didn’t see this sooner! Please contact our webstore and they will fix the shipment. The soap bottles have an induction seal, but the hair rinse only have a foam insert. I’m not sure why that is.

  9. Can i use Dr Bronner castile Bar soap on my hair directly ?? Which is the best castile bar soap between Citrus orange & peppermint ?

    After washing with the Bar soap , should i need to compulsory use hair rinse ?? When can i use style creme ??

    • Hi Sanjay – There is so much here that is specific to hair type. There are many people out there who don’t use anything but the soap on their hair and have for years. The bar soap cleans just as well as the liquid. My preference for the liquid is really a time thing – it takes a lot longer to work enough soap off the bar and into my hair to get a good lather. But I have really long hair. My boys and husband, on the other hand, use only the bar and lather from head to toe all at once and are good to go. As for a rinse, if you need it, use it. If you find afterwards that your hair feels slightly tacky, even when dry, or isn’t as smooth as it should be, the problem is probably that you need the pH balancing of the acidic hair rinse. Instead of the hair rinse, a 50% solution of apple cider vinegar has a similar effect. Again, my husband and boys do not need the hair rinse and are fine with the soap alone.

      There are so many different types of hair out there that it definitely takes some experimentation. Good luck!

  10. What kind of process used to make the bar soap? Is it cold process or melt and pour, or other?!

    • Hi there – Our bar soaps are made by a “triple-milled” process, meaning that after the soap is made, it is dried into crystals, then rolled at least three times between large stainless steel rollers until a paste is formed. The resulting paste is then pressed into soap molds, and the triple milled bar soap is created.

  11. Which soap should I use for delicate clothes such as bras, panties, & items such as these ?

    • Hi Doris – I prefer to use our Sal Suds Biodegradable Cleaner for these delicate items. It is very mild and super clean rinsing, which is best for delicate items, especially those which contain elastic.

  12. I didn’t see you mention a major difference between the two soaps, which is that the liquid soap does not contain sodium, and so can be used outdoors or in the garden. At least I am hoping this is still true, because now I see that palm kernel oil has been added to the liquid soap, so I hope it does not affect use outdoors near plants or in the garden.

    • Hi Kathy – Great point! Thanks for bring that up. As water shortages increase, many people are looking to grey water systems. We had our soaps certified for grey water system safety quite a few years ago. I have the certificates if you’d like to see them. Email me at

  13. My question has disappeared, so I will retype it: Can the liquid Dr. Bronner’s soap still be used in the garden? I noticed that palm kernel oil has been added to the ingredient list, so I just wanted to make sure that the liquid soap is still usable as insecticidal soap, or just as part of grey water on plants. It doesn’t have sodium, as the bar soap does, so I know people that used the old formulation in the garden. Thanks for your help.

    • Hi Kathy – The Palm Kernel Oil does not affect its use in the garden. It’s still safe for grey water systems.

  14. The palm kernel oil in your liquid soap, is it sourced from Ghana or Equador?

    • Hi Sarah – Our palm kernel oil comes from Ecuador and is sourced through Natural Habitats, which is certified under IMO’s Fair for Life, the most rigorous Fair Trade and sustainable certification in the world. Fair for Life also certifies Dr. Bronner’s. You didn’t ask, but since you got me started, check out this new venture from Natural Habitats called “Palm Done Right” about how palm oil production can happen without destruction to the environment, habitat loss, or worker exploitation: Our palm oil, which we use in our bar soaps, is from our sister company Serendipalm, located in Assoum, Ghana. You can check out more about that awesome operation here:

  15. I have a question. Do all of your soaps contain citric acid? I have a severe reaction to it, as well as most other chemicals.
    Thank you!

    • Thank you so much for getting back to me. I react to most products so I have to be very careful about trying something new. I appreciate you researching this for me.
      Thanks again,

    • Hi Donal – Yes, they’re safe for psoriasis and the Eucalyptus and Tea Tree have gotten customer feedback saying that they may even alleviate some of the symptoms.

    • Hi Mark – I love talking about density! No, the bar soap does not float. Its density is slightly higher than that of water, so it sinks. The only bar soap that I know of that floats is Dove because it has air whipped into it. Just out of curiosity, why do you ask?

  16. I bought a large container of Dr. B liquid soap and it seems to be too thin for my usual soap pump. Are the Dr. B pump soaps the same consistency as the liquid soaps, or are those thicker to suit the pump mechanism? Thanks!

    • Hi Paul – We formulated the Pump Soaps because there was so much customer call for soaps that worked in pumps. As you’ve seen, our Pure Castile soaps do not. They are the wrong consistency and changing that requires a good bit of reformulation. That’s how we ended up with the Pump Soaps. The Pure Castile soaps also inevitably clog the pump by drying out in them and creating a blockage that squirts the soap out in unexpected directions. If this hasn’t happened to you yet, just take my word for it. It’ll undoubtedly happen to the next person you have over that you’re trying to impress. I speak from experience.

  17. Hi, I found on few website that the liquid soap was use by some as toothpaste. Would it be the same thing using a bar soap? And is it actually safe? Thanks

  18. Hello. I recently purchased a 2-ounce travel-size soap. It was not sealed. This surprised me as all of the other bottles, albeit larger sizes, that I have purchased in the past have been sealed. Are the travel-size bottles sold unsealed? Thank you in advance.

  19. Hi Lisa,
    I’ve been using the liquid castile soap for years and I love it, however when using it in the shower, in order to get a nice lather out of a few drops, I have to use a plastic mesh shower puff. I’d much prefer to use something not made from plastic.
    I recently crocheted a cotton shower puff but when I attempted to use it I ran out of soap on it and I had to end up using so much more. Can you think of any solution to this?
    Appreciate any help you can provide!

  20. Hi! I just purchased one of your bar soaps. I understand that we are required to add water to the castille liquid soap before using it. Are we supposed to do that or can we use the bar soap directly for shower?

  21. Hi Lisa, what percentage of hemp oil would you estimate makes up the Bronner’s bar soaps?

  22. Hi Lisa,
    Thank you so much for your time andf ountain of information! I clean primarily with Dawn (original), baking soda, and vinegar. Baking soda in the Dawn, rinse with water, spritz with vinegar. Or spray bottle with vinegar and a tiny amount of Dawn. I would like to convert to using Bronners, what would you suggest? Replace the Dawn? Mix with BS & vinegar ok?? Thank you!

  23. Hi Lisa,
    Thank you so much for your time and fountain of information! I clean primarily with Dawn (original), baking soda, and vinegar. Baking soda in the Dawn, rinse with water, spritz with vinegar. Or spray bottle with vinegar and a tiny amount of Dawn. I would like to convert to using Bronners, what would you suggest? Replace the Dawn? Mix with BS & vinegar ok?? Thank you!
    (Previous submission had wrong email, sorry!)

  24. Hi! I was just wondering what the pH level are on these 2 products, more specifically, if they are the same or not

    • Hi Andry – The pH of our liquid castile soaps is 9.75-10. The pH of our bar soap is 10.0 – 10.5.

  25. I just wanted to share my recipe for turning bar soap into body wash and laundry powder.

    Body wash : 1 bar of soap, grated
    3 litres of water
    2 tablespoons of glycerin
    Add the grated soap to 3 litres of water. Let it simmer until all the soap has melted. Turn off the heat and add 2 tablespoons of glycerin. Mix well and cover. Set aside for 24 hours to set. Mix well and fill pump bottles.
    I use this for my body wash and hand wash. If it gets a bit thick just shake it up or add a little water if needed.
    Store remaining body wash in a sealed container. I use an ice cream container.

    Laundry powder : 1 bar of soap, grated
    4 cups of baking soda
    3 cups of washing soda
    Pulse the grated soap in a food processor with some of the baking soda to make the soap finer.
    Add the rest of the ingredients and mix until well combined. I use 1 tablespoon per wash (2 if it’s a dirty/heavy load). I mix it with a bit of water first then add the machine. I have a front loader. I also use vinegar as fabric softener. It prevents the machine from getting clogged aswell.

  26. Time for true confessions, folks. It is February 9, 2017, and I have missed several months of comments for the simple reasons that things went a little crazy around here. I very much apologize. I am tackling them now for the sake of those faithful and new readers who might actually read them all. I am going to start with the most recent. Bear with me.

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